CCAST, World Lab, Beijing 100080, Peoples R China
; Chinese Acad Sci, Shanghai Inst Nucl Res, Shanghai 201800, Peoples R China
; Natl Lab Heavy Ion Accelerator Lanzhou, Res Ctr Nucl Theory, Lanzhou 730000, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China
We have studied the evolution and dilepton production of a chemically equilibrating quark-gluon system at finite baryon density. We found that due to the increase of the quark phase lifetime with increasing initial quark chemical potential and other factors, such as, higher initial temperature, larger gluon density, and gluon fusion or quark annihilation cross section, thermal charmed quarks provide a dominant contribution to the dilepton yield. This results in a significant enhancement of intermediate mass dilepton production.